The invention relates to an impact screwdriver having a housing in which an impact mechanism having a hammer is accommodated, said hammer interacting with an anvil to drive a tool, wherein the hammer is accommodated on a drive shaft so as to be axially movable and preloaded in the axial direction, and wherein the hammer is driven by the drive shaft via a driver and is preloaded counter to the force of a spring element in order to trip when a particular rotation angle is exceeded and transmit a rotary impulse to the anvil.
An impact screwdriver of this type is known from DE 10 2013 021 202 A1. The known screwdriver is configured to tighten screw connections but does not have a measuring device in order to be able to set a predetermined tightening torque.
DE 31 28 558 A1 discloses a further impact screwdriver, in which the duration of the impact impulses is continually measured and compared with a predetermined minimum impulse duration associated with the desired final torque, and the impact screwdriver is switched off when an impact impulse duration corresponding to the minimum impulse duration is reached. In this case, the impulse duration is measured via a magnetic switch and compared with the minimum impulse duration.
Monitoring of the impact impulse duration by means of a magnetic switch is relatively complicated, both in terms of production and in terms of assembly. Alternatively, the switch is also said to be able to be embodied as an electric or electronic switch, but no disclosure is given as to how such a switch is configured.